1. Field of the Invention
The present invention relates to piezoelectric actuators that convert electric signal to a mechanical output, and carriers and shake correction apparatus in cameras that use the actuator.
2. Background Art
Conventional piezoelectric actuators comprise an elastic column, a projection provided at the center of a front surface of the column, a first pair of piezoelectric elements each bonded to the front surface of the column on a respective one of opposite sides of the projection and a second pair of piezoelectric elements each bonded to a back surface of the column so as to correspond in position to the first pair of piezoelectric elements. When prescribed different voltages are applied across the respective piezoelectric elements, these piezoelectric element extend or contract, thereby deforming the column, which causes the projection to deviate in vertical and horizontal planes, thereby moving an object of interest in corresponding desired directions, for example, as disclosed in Unexamined Japanese Patent Publication 7-274556.
The arrangement of the first and second pairs of piezoelectric elements on the elastic column allows the projection to deviate only in horizontal directions in a plane which intersects with the projection when no voltages are applied to the first and second pairs of piezoelectric elements.
It is therefore an object of the present invention to provide a piezoelectric actuator enabling the projection to deviate in any directions in a plane which intersects with the projection.